Photovoltaic (PV) power generation systems are power systems that employ a plurality of solar modules to convert sunlight into electricity. PV systems include multiple components, including photovoltaic modules, mechanical and electrical connections and mountings, and signal conditioners for regulating or modifying the electrical output. In some examples, several PV modules are connected in series to form a PV string, with multiple PV strings in a PV system then being combined in parallel to aggregate the current in a PV array. PV cells generate direct current (DC) power, with the level of DC power being dependent on solar irradiation and the level of DC voltage dependent on temperature. When alternating current (AC) power is desired, an inverter is used to convert the DC power into AC power, such as AC power suitable for transfer to a power grid.
PV power systems have a complex relationship between their operating environment and the maximum power they can produce. A Fill Factor (FF) is a parameter that characterizes a non-linear electrical behavior of a solar cell of the PV power system. The FF is defined as the ratio of the maximum power from the solar cell to the product of Open Circuit Voltage (VOC) and Short-Circuit Current (ISC). In tabulated data, the FF is employed to estimate the maximum power that a PV cell can provide with an optimal load under given conditions.